docs: def handle(self, site=None, **options):
          """
          Export pages in JSON format.  Site may be specified by id or domain.
          Default: export pages from the current site specified by settings.SITE_ID.
          """
          if options['all_sites']:
              monkeypatch_remove_pages_site_restrictions()
          qs = Page.objects.all()
          if site:
              for match in ('pk', 'domain'):
                  try:
                      s = Site.objects.get(**{match:site})
                      break
                  except (Site.objects.DoesNotExist, ValueError):
                      continue
              else:
                  raise CommandError(_("Site with id/domain = '%s' not found")
                      % site)
              qs.filter(site=s)
  
          sys.stdout.write(pages_to_json(qs))